Answer:
B. \ kə-lŏs'-əs \
Step-by-step explanation:
A may look to be the answer at first glance, but it actually tells you how to "divide" the word up into syllables, not how to pronounce it; this part of the dictionary entry is very helpful if you need to hyphenate the word when you're writing.
B looks to be a promising answer. Whenever you see Latin symbols near the top of the dictionary entry, it is the pronunciation of the word based on an alphabetic system called the IPA, or International Phonetic Alphabet.
C is one of the many definitions of colossus, so that is not the answer.
D is the part of speech of the word defined.