When Daniel Janzen studied the ant-acacia system by removing ant colonies from some acacias, he found much lower growth rates in the acacia after ants were removed. Which other changes were seen in the responses of the acacia to ant removal?

A) Their survival rate was higher and they were more susceptible to insect herbivores.
B) Their survival rate was higher and they were less susceptible to insect herbivores.
C) Their survival rate was lower and they were more susceptible to insect herbivores.
D) Their survival rate was lower and they were less susceptible to insect herbivores.