Why is it possible that EGFR can transmit more than one type of signals once it's activated. Because________________. a. Activated EGFR can cross communicate with other types of RTKs. b. EGFR can be activated by several different ligands (primary messengers) c. Activated EGFR can activate several different adaptor proteins through SH2 domain d. EGFR can interact with different intracellular adaptor proteins without EGF binding e. Activated EGFR can interact with other proteins via regulatory subunit