Task: Question Answering
Input (English): Question: The proteins can exhibit a fluorescent emission spectrum due to the presence of the following intrinsic fluorophores that absorb radiation in the UV-next region: 
 Options:  <1> Alanine, valine, glycine. <2> Tryptophan, tyrosine, phenylalanine. <3> Serine, methionine, asparagine. <4> Cysteine, alanine, methionine. <5> None of the above is correct, proteins never exhibit fluorescence.
Output (English): 2