Final answer:
The measure of ∠KMC is 43 degrees. The correct answer is A.
Step-by-step explanation:
To find the measure of ∠KMC, we need to know that KM bisects ∠ABC. This means that ∠ABC is divided into two equal angles, and each of those angles is ∠CMK and ∠KMC. Since ∠ABC measures 86 degrees, each of the bisection angles, including ∠KMC, will have a measure of 86 degrees ÷ 2 = 43 degrees. Therefore, the correct answer is A. 43 degrees.
If KM bisects ∠ABC and the measure of ∠ABC is 86 degrees, then ∠KMC would be half the measure of ∠ABC, since bisect means to divide into two equal parts. Therefore, the measure of ∠KMC is 43 degrees. The correct answer is A.