Why is gravity filtration not used for collecting crystals, and why is filter paper necessary for a frit?
a) Gravity filtration is too slow, and filter paper prevents contamination.
b) Gravity filtration is not efficient, and filter paper prevents loss of product.
c) Gravity filtration does not remove fine particles, and filter paper provides support.
d) Gravity filtration does not remove impurities, and filter paper promotes crystallization.