Who Is "A"? Our Prime Suspect List

Why it's possible:

• Listen, Mona's crazy. Always has been, always will be. We've come to realize she was insane long before she took over as "A" and long before her stint at Radley.
• She's already been revealed as a member of the "A" team, and she could still be on it. Plus, she knew Ali was alive this whole time, so she'd surely have the upper hand.
• Let's not forget that weird scene with Wren, where she talks about loyalty and secrets.

Why it's not:

• We've seen Mona cross over to the good side already. Plus, she says someone took the game from her while she was in Radley.
• Mona's been put in clear danger by "A" before (like during the lodge fire).
• She didn't know who Red Coat was.

Source: ABC Family