Consider a mutant bacterium you have isolated which is unable to synthesize the amino acid tyrosine. You grow it in the presence of a chemical mutagen and isolate a single revertant, which is now able to grow in the absence of tyrosine (i.e. it can once again make its own). You determine that the suppressing mutation is not in the original mutated gene, but is instead in a tRNA gene. Which of the following types of mutation might the original mutation be? For each possibility listed below, explain your reasoning (more than one of these may be correct).

point mutation

deletion mutation

insertion mutation

missense mutation

nonsense mutation

Please SHOW and EXPLAIN all work.