Final answer:
The correct words for the sentence are their/they're or there/they're.
Step-by-step explanation:
The correct words for the sentence:
Their/they're
There/they're
Scream/for a
Think/upon
They're/there
They're/their
In this sentence, the correct words to choose as a replacement for "happy to wish" would be "Their/they're" or "There/they're". The sentence could be either: "Their best friend a Merry Halloween and a Happy Christmas..." or "There best friend a Merry Halloween and a Happy Christmas..." depending on what the intended meaning is. The other options provided in the question are not suitable replacements for the given sentence.
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