Parity bit assignment — odd parity for a given data word For the 6-bit data word 111001, append a single odd parity bit at the most significant end (left) so that the total count of 1s is odd. What is the resulting 7-bit code?

Introduction / Context:
Parity is a classic single-bit error-detection method used in memory systems, serial links, and simple buses. With odd parity, we choose the parity bit so that the total number of 1s across data plus parity is odd. This problem reinforces where to place the parity bit and how to compute its value for a specific data word.

Given Data / Assumptions:

• Data word: 111001 (6 bits).
• Parity scheme: odd parity.
• Placement convention: parity bit is appended at the most significant end (left side).

Concept / Approach:
Count the number of 1s in the data word. If the count is already odd, parity bit = 0. If it is even, parity bit = 1 to make the overall count odd. After deciding the parity bit, place it on the left as specified and keep the original data bit order unchanged.

Step-by-Step Solution:

Verification / Alternative check:
Total ones in 1111001 are 5, which is odd, satisfying the odd parity rule. No data bits were rearranged; only a single parity bit was added at the left.

Why Other Options Are Wrong:

• 1111011, 0111111, 0011111: these either change the original data pattern or place/compute the parity bit incorrectly, yielding the wrong total count or wrong placement.

Common Pitfalls:
Appending the parity bit to the right when the convention states left, miscounting 1s, or flipping a data bit instead of adding a new bit.

Final Answer:
1111001