Let's break down each question to understand why the given answers are correct:

### Question 1: Tuple as a Data Type

- **Explanation:** In the context of AP Computer Science Principles, the course focuses on foundational concepts in computer science and typically emphasizes data types that are fundamental to programming and problem solving, such as strings, integers, and Booleans. Tuples, while a common data structure in languages like Python, are not explicitly covered as a fundamental data type in the AP Principles curriculum, which is why "Tuple" is the correct choice as not being a part of the AP Principles data types.

### Question 2: Definition of an Algorithm

- **Explanation:** An algorithm is indeed a methodical set of steps designed to perform a task or solve a problem. This definition encompasses the essence of algorithms in computer science and programming, differentiating it from the other options which relate to aspects not directly defining what an algorithm is.

### Question 3: Data Structure for Create Task

- **Explanation:** For the Create Task in AP Computer Science Principles, students are often encouraged to utilize data structures that allow for dynamic data management and easy manipulation. Lists are versatile, allowing for addition, removal, and modification of elements, making them ideal for a wide range of programming tasks in the course.

### Question 4: Purpose of Debugging

- **Explanation:** Debugging is a critical part of the programming process, aimed at identifying and resolving errors or "bugs" in code. This ensures that the software functions as intended, differentiating it from other activities like optimization (speed enhancement) or compilation (converting to machine language).

### Question 5: Logical Error

- **Explanation:** A semantic error, or logical error, occurs when a program runs without crashing but produces incorrect results. These errors are due to flaws in the logic of the program, distinguishing them from syntax errors (coding grammar mistakes), runtime errors (errors that occur during execution), and compilation errors (errors detected during compilation).

### Question 6: Main Goal of Testing Code

- **Explanation:** Testing is essential to ensure that a program performs correctly across a range of conditions and inputs. It's not just about preventing crashes but about confirming that the software meets its specifications and requirements.

### Question 7: Common Testing Method

- **Explanation:** Syntax testing is not a standard testing methodology. Common methods include unit testing (testing individual components), integration testing (testing combined components), and system testing (testing the complete system). Syntax checks are typically part of the development (coding) process rather than a separate testing phase.

### Question 8: Iteration in Programming

- **Explanation:** Iteration is fundamental in programming, enabling repetitive execution of code blocks, such as loops, until a certain condition is satisfied or a specific number of repetitions is completed.

### Question 9: Boolean Data Type

- **Explanation:** The Boolean data type is used to represent true/false or yes/no conditions in programming, crucial for control flow and decision-making processes.

### Question 10: Algorithm's Efficiency

- **Explanation:** Efficiency of an algorithm is gauged by how quickly and resource-effectively it can resolve a problem, highlighting the importance of optimized coding practices for performance and resource management.

### Question 11: Purpose of a Variable

- **Explanation:** Variables are fundamental in programming, serving as placeholders for data that can be accessed and manipulated throughout the execution of a program, enabling dynamic and flexible coding practices.

### Question 12: High-Level Programming Language

- **Explanation:** Python is an example of a high-level programming language, designed to be easily readable and writable by humans, abstracting away much of the complexity of machine code or lower-level languages like Assembly.

### Question 13: Syntax in Programming

- **Explanation:** Syntax refers to the set of rules that define the correct structure and composition of statements in a programming language, similar to grammar in human languages.

### Question 14: Mutable Data Structures

- **Explanation:** Mutability refers to the ability of a data structure to be altered post-creation, including changes to its size, content, or structure, distinguishing mutable structures from immutable ones.

### Question 15: Using Comments in Code

- **Explanation:** Comments are used in programming to annotate code, offering explanations, clarifications, or notes for developers, thereby enhancing the readability and maintainability of the code without affecting its execution.