Question

Which of the following does not describe BLAST?

(a) It stands for Basic Local Alignment Search Tool

(b) It uses word matching like FASTA

(c) It is one of the tools of the NCBI

(d) Even if no words are similar, there is an alignment to be considered

The question was asked during an interview.

Question is taken from Local Sequence Alignment in section Sequence Alignment of Bioinformatics

Answer 1

Right answer is (d) Even if no words are similar, there is an alignment to be considered

To explain I would say: If no words are similar, there is no alignment i. e. it will not find matches for very short sequences. But it is considerably accurate as compared to other tools and hence is quite popular.