Correct option is B
Given:
In right triangle ABC with right angle at C, M is the mid-point of hypotenuse AB. C
is joined to M and produced to a point D, such that DM = CM. Point D is joined to B. If
CD = 10 cm, and BD = 6 cm.
Concept Used :
DBC is a right angled triangle Triangle ABC and DBC are congruent and and CM = 1/2 AB = CD

Solution:
∴ CM =