Which is an advantage of producing genetically engineered crops that have pest-resistant genes?
bioaccumulation of crops over time
allows farmers to grow any crop they want
reduces the use of pesticides for certain insects
gene transfer to nontarget species

The correct answer would be "reduces the use of pesticides for certain insects".

Genetic engineered plants are those which are genetically modified by introducing a foreign gene in them. The foreign gene provides the plants with characters such as high yield, pest resistance, high shelf life et cetera.

Pest-resistance ability enables the crops or plants to resist the growth or invasions of pests.  

For example, Bt cotton is a genetically modified crop made by inserting a gene (cry gene) from bacterium Bacillus thuringiensis. This gene encodes for insecticidal toxins that make the Bt cotton resistant against butterflies and moths, cotton bollworms, beetles et cetera.

Thus, pest resistance gene reduces the dependency of farmers on pesticides.