The answer is C for this question....
1) C
2) A
all would be a risk due to swallowing puzzle pieces little kids put everything in their mouths. my thoughts
Starting with the hardest it would be corundum, feldspar, apatite, calcite, talc.
He could have homogeneous genes, both being the brown eyed gene. Or he could be heterogeneous, one parent having the brown eyed gene and the other would be a different eye color.