Which statement best describes the differences between GPCR and RTK activation of phosphoinositide signaling pathways?

• A. RTKs primarily lead to calcium signaling, while GPCRs are involved in cell division and survival.
• B. Both GPCRs and RTKs lead to identical cellular functions.
• C. GPCRs and RTKs do not activate phosphoinositide signaling pathways.
• D. GPCRs primarily lead to calcium signaling, while RTKs are involved in cell division and survival.

Answer: (D)