9514 1404 393
Answer:
 A.  r = 4
Step-by-step explanation:
For common ratio r, the second term is ...
 a2 = 3r
The next terms are ...
 a3 = (a2)r = (3r)r = 3r²
 a4 = (a3)r = (3r²)r = 3r³ = 192
Then the value of r is ...
 r³ = 192/3 = 64
 r = ∛64 = 4
The common ratio is r = 4.