Respuesta :
I think the answer is D. I'm in 7th grade too. I'd go with either D. or A.
The correct answer is actually A. Toe dancing was developed in the early nineteenth century, but it was not widely used until the 1830s.
A comma splice incorrectly connects two independent clauses - where there should be a conjunction, a comma is incorrectly placed, like in the example above.
B is incorrect because the only thing that changed was that the comma was deleted - it didn't actually fix anything; C is incorrect because the subject is missing after yet - it should be: ...yet IT was not widely used... D is incorrect because there should be a semicolon (;) in front of however and not a comma.