Answer : 1. "amino acids"
Explanation :

Answer: A) amino acids Explanation: It is the fact that all type of proteins are polymers of amino acids. So that, plants are also used to synthesise protein from amino acids.    Plants synthesis protein from amino acids in the presence of ATP by specific synthetases. This reaction is followed by the attachment of these activated amino acids to specific tRNA molecules, with the formation of aminoacyl-tRNA molecules.