I think that the answer is A
Answer:
Intercellular communication refers to the communication between cells. Membrane vesicle trafficking has an important role in intercellular communications in humans and animals, e.g., in synaptic transmission, hormone secretion via vesicular exocytosis.
B
The Ardi fossil is believed to be 4.4 million years old, providing evidence that humans have been on Earth for 4 million years.
-- Charges with the same sign repel each other.
-- Charges with different signs attract each other.
-- This is called the "electrostatic force".
-- There's another set of forces called "magnetic forces", but
-- there's no such thing as "electromagnetic force".