The answer is B. 0.82 M BaCl2
How to generate the answer:
Let:
n = amount of substance
V = volume of solution
Equation for n:
n (BaCl2) = 0.98 mol. (unit of mole)
Equation for V:
V (solution) = 1.2L
Required:
c(BaCl2) =?
Equation for the whole problem:
c(BaCl2) = n (BaCl2) / V (solution)
c(BaCl2) = 0.98 mol / 1.2L
c(BaCl2) = 0.82 mol/L
= 0.82 M
Thus,
the resulting molarity is 0.82 M BaCl2