Need help on selective learning

[MadhuIndia]

My DD1 (9 years) is good at so many things. Karate, Swimming, Math, Science, Reading. Her hobbies include Pencil Drawing, Sing Along. My DD2(5 years) is good at reading and tries to copy whatever her sis does. 

Suggestions needed.

My DD1 is not interested in learning Social Studies and Second Language. She reads the subjects just for her teachers and tests. 

1. Should I let her to pursue her interest or should I talk to her the importance of Social Studies and Second language?

2. What is the right age to let the child to choose the subject she likes? 

Thanks,
Madhu

[MadhuIndia]

Thanks for your reply.

Social Studies - She likes to know about places and people. But she is not interested in reading it in depth. 

For Second Language - She started learning by reading story books. She reads her lessons and tries translating them to english. She communicates in simple sentences.

Unless I sit with her to spend time on those subjects, she doesn't spend time on them.  The point is, she gets B grade in these two subjects. In all other subjects she gets A+. I am happy with that B+ grades. I don't want to force her to be good in everything. Her teacher says she might develop interest in these subjects over the years and I can wait. I am sure if I spend more time, she should be good at those subjects.

My question is should I spend more time with her to get her in A grade category?  Or should I let her to be average? If I let her to be just average in few subjects, what will I be missing out? Later I shouldn't regret I wish I had known this. 

Thanks,
Madhu