Final answer:
Genes that are advantageous but not critical for survival are known as non-essential genes (option 4). They offer benefits which can lead to an organism's better adaptation and possible advantageous evolution.
Step-by-step explanation:
Genes that are not required for survival, but are likely to be beneficial to the organism, are called non-essential genes. While a large proportion of an individual's genome comprises essential genes necessary for survival, non-essential genes don't serve critical functions yet may provide advantages in certain environments. This contrasts with essential genes, where even a single nonfunctional allele can lead to deleterious effects, such as in the case of recessive lethal inheritance patterns.
Beneficial mutations can lead to the rise of non-essential genes that confer an advantage, such as resistance to diseases or the capacity to thrive in varying environmental conditions, aiding an organism's adaption overt time.