NEED HELP ASAP PLEASE!

Combine the following expressions.

1) √48n^3 + √9n - √3n

A) (4n - 1)√3n - 3√n
B) (4n - 1)√3n + 3√n
C) 3n√3n + 3√n

2) r√t + s√t

A) √rs + 2t
B) (r-s)√t
C) (r+s)√t