題目：
You can download an entire album of songs or choose just the songs that you like
. With all the music that you ________stored in your MP3 player, you can take it
with you everywhere. Then you can choose to listen to the music that suits your
mood.
(A) favoring
(B) favored
(C) favors
(D) favor
疑問:
⑴請問答案為何是D?
⑵請問為何stored 是用過去式？如果是被動語態的話不用加be動詞嗎？
還請大家多多幫忙，謝謝