The product of the variables s and t, with s equal to -8 and t equal to 3/4, is -6. This is computed simply by multiplying -8 by 3/4.
The question asks for the product of two variables s and t, given that s = -8 and t = 3/4. When we substitute these values into the expression st, we get:
st = (-8) * (3/4)
Multiplying these together, we get a new value:
st = -8 * ⅓ = -6
The final answer is that the product of -8 and 3/4 is -6, which corresponds to option c.