Clearing (turning off) one or more bits using bitwise AND in conjunction with bitwise NOT: is the pattern x &= ~mask correct?

Introduction / Context:
Clearing bits is the counterpart to setting bits. It is used in configuration registers, permission systems, and toggling flags off. The standard pattern leverages bitwise NOT to invert a mask and then AND to force target positions to 0.

Given Data / Assumptions:

• x is an integer value.
• mask has 1s in the positions we want to clear in x.
• We apply x &= ~mask.

Concept / Approach:
Bitwise NOT (~mask) flips 1s to 0s and 0s to 1s. When we AND x with ~mask, any positions where mask had 1 become 0 in the result (since 0 & anything = 0). All other positions pass through unchanged (1 & bit = bit). This reliably clears the selected bits regardless of their prior state.

Step-by-Step Solution:

Verification / Alternative check:
Example: x=0b1111, mask=0b0101 → ~mask=0b1010 → x & ~mask = 0b1010, clearing bits 0 and 2 as intended.

Why Other Options Are Wrong:

Common Pitfalls:
Building the mask incorrectly; using XOR when you meant to clear; forgetting parentheses in complex expressions.

Final Answer:
Yes — x = x & ~mask clears the bits that are 1 in mask.