This is not math
im not sure what this answer is specifically you can look it up on line
"cause and effect of mountains and deserts"
The GCF is based upon what integer divides evenly into two numbers; the LCM is based upon what integer two numbers share in a list of multiples. The GCF must be a prime number; the LCM must be a composite number.
Times both sides by 10
(10g)/10=-9*10
(10/10)g=-90
1g=-90
g=-90
B,C and D are correct because all of those choices include letters which are arranged in order from left of right.