To say that something is "good" or "strong" is not

a. subjective, because these words can't be defined
b. objective, because the definitions of these words depend on feelings or judgments
c. subjective, because these words are indicators that the person who uses them is making a statement of quality
d. appropriate for the media and automatically makes a message invalid and not usable

b. objective

Explanation:

To say that someone is 'good' or 'strong' is not objective because it is based on your own values, perceptions and judgement.  So, someone else might have a very different perception of those adjectives based on his own experience and values.

It's not objective, it's subjective, because it depends of the subject (individual) saying those words, on what they define is good, on what they believe is strong and so on.

Objective means it's something that everyone agrees on, that has a general consensus among the population.  For example, saying someone is beautiful/handsome implies your own criteria of beauty, which may or may not be shared by others.  But if you say someone is tall, then it can be measured and quantified to determine if it's really the case or not, it's not dependent on someone's opinion or feelings.

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