Considering the following statements;
A. The trait is the same for all organisms
B. The trait is resistant to mutations
C. Most forms of the trait have the same impact on survival
D. The trait is passed on genetically to the next generation
The correct answer is D.
Genetic variation is essential for natural selection since natural selection can only increase or decrease frequency of alleles that already exist in the population. Genetic variation is caused by mutation and random mating organisms.
B.
Homogeneous means one mixture, so like salt water. It looks like one mixture.
Heterogenous means different mixture. Comparable to a bag of Chex mix. So if the magnet can attract the pieces of Iron, it has to be a separable mixture. Compounds would require a chemical reaction to separate.
They must occur in the DNA, which is in each cells nucleus. More specifically the nucleolus of the cell. A mutation occurs in an allele, where a base triplet (or a codon) gets transcribed incorrectly.