Answer:
B
Step-by-step explanation:
A: is incorrect. YOu can't mix a participle (sewing) with an infinitive. (to swim)
B: looks correct, but I'm not sure that modern grammar needs a comma after swimming. Let's just see.
C: No to horseback ride is not only an infinitive, it is a split infinitive. There are two errors.
D: Wrong. The horseback riding is a participle. The others are infinitives. They don't mix.