A male carrier of a recessive somatic mutation marries a female without this mutation. What is the probability that their child will be a carrier?

A. 0%

B. 25%

C. 50%

D. 100%

The probability that their child will be a carrier can be calculated using Punnett square analysis.

If the male carrier has the genotype Aa (A representing the normal allele and a representing the recessive allele), and the female does not have the mutation (genotype AA), the possible genotypes of their child will be:

- Aa: 50% chance (child inherits one recessive allele from the male carrier)
- AA: 50% chance (child inherits one normal allele from the male carrier)

Since the child has a 50% chance of inheriting the recessive allele from the male carrier, the probability that the child will be a carrier is 50%.

Therefore, the answer is C. 50%.