Determine which of the following logarithms is condensed correctly

The laws of logarithm has specific theories to be applied depending on the form of the given expression. Some of it are the following:

alogb = log b^a
log a + log b = log (ab)
log a - log b = log (a/b)

for letter A,
xlogb r + logb s - logb t = logb [(rs)^x]/t
is wrong because the s part from logb s has no x before the logb

for letter B,
xlogb r + xlogb s - logb t = logb (rs/t)^x
is wrong because the t part from logb t has no x before logb

for letter C,
logbr - xlogb s + xlogb t = logb (r)/(st)^x
is correct because after the minus sign, condensing it would form a fraction, the plus sign will form a multiplication and both s and t are raised to the power of x.
So the answer is letter C.

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