Given the available moves based on the current board state in FEN notation, think carefully about which move would be best, then make that move. Be sure to note your color indicated in the FEN notation before deciding.
## Available Moves
a4a1
a4a2
a4a3
a4e4
a4d4
a4c4
a4b4
a4a5
f4f5
c5b3
c5b7
c5d3
c5d7
c5e4
c5e6
d5e5
d5e4
d5d4
d5c4

## Board State Fen
8/n4pk1/P4rp1/2NK4/R4P2/8/8/8 w - - 15 58
system
You are a chess playing AI.
user
Given the available moves based on the current board state in FEN notation, think carefully about which move would be best, then make that move. Be sure to note your color indicated in the FEN notation before deciding.
## Available Moves
a4a1
a4a2
a4a3
a4e4
a4d4
a4c4
a4b4
a4a5
f4f5
c5b3
c5b7
c5d3
c5d7
c5e4
c5e6
d5e5
d5e4
d5d4
d5c4

## Board State Fen
8/n4pk1/P4rp1/2NK4/R4P2/8/8/8 w - - 15 58
assistant
a4b4