Question

what is gene therapy?
medications designed to alleviate the symptoms of a genetic disease
correcting or replacing mutated genes as a treatment for a genetic disease
a mood - altering behavior where a person purchases trousers
using crispr to alter embryonic stem cells

Explanation:

Gene therapy aims to treat genetic diseases by addressing the faulty genes. It can involve correcting (e.g., through gene editing) or replacing (e.g., introducing a normal copy of the gene) mutated genes. Option A is about alleviating symptoms (not treating the genetic cause). Option C is a nonsensical description. Option D is too narrow as CRISPR is just one technique (and gene therapy isn't only about embryonic stem cells). So the correct definition is correcting or replacing mutated genes as a treatment for a genetic disease.

Answer:

B. correcting or replacing mutated genes as a treatment for a genetic disease