Mark the letter A, B, C or D to indicate the correct sentence formed by the given words.
I/ be / proud/ my sister / because/ she/ always / study well.
A.
I am very proud of my sister because she always studies well.
B.
I’m very proud my sister because she studies always well.
C.
I am very proud of my sister because she always study well.
D.
I am very proud my sister because she always studies well.