In English we can say, "still more" in that word order to mean the same (even more or yet more), which is different from, "more still" (still has some).
So that is my humble explanation why, "still more" should be accepted as a possible answer to this exercise. :)
- Massa is said with the same vowels as "pasta". (First syllable stressed)
http://pt.forvo.com/word/massa/#pt (she is from Spain, but her pronounce is perfect for Brazilian "massa")
- Maçã has the second syllable stressed, and ends somewhat like "sun" (English). Something like mah-sun.
http://pt.forvo.com/word/ma%C3%A7%C3%A3/#pt (again, thatra's pronunciation is very good, it's slow and easy to undesrtand. Other good pronunciations are from: ilogicant, coohrus and hiroy. Some others are trying to separate syllables so clearly that the stressing of the last one fails)