Answer: b

Explanation:
Most style guides discourage the use of Xmas, probably because many people find it offensive.

In fact, Xmas is a variation on Christmas that has deep roots. From Wikipedia:

 Early use of “Xmas” includes Bernard Ward’s History of St. Edmund’s college, Old Hall (originally published circa 1755).^[9] An earlier version, “X’temmas”, dates to 1551.^[9] Around 1100 the term was written as “Xp̄es mæsse” in the Anglo-Saxon Chronicle.^[2] ”Xmas” is found in a letter from George Woodward in 1753.^[10] Lord Byron used the term in 1811,^[11] as did Samuel Coleridge (1801)^[5] and Lewis Carroll (1864).^[11]

Many Christians object to Xmas because they believe it removes Christ’s name from the word. However,  According to the OED, the use of the letter X to refer to Christ goes back to 1485.

In any case, however, let’s maintain the peace this season by refraining from using Xmas.

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b. fourth of July

Answer: a.

Explanation:

In the U.S., writers capitalize “fourth” in “Fourth of July” because it’s a special date. Although the official name of the holiday is “Independence Day,” we capitalize “fouth” to identify it with the holiday, so readers realize it has some significance. In this case, hackers thought it would be an especially swell day to attack a government website.

Of course, you only capitalize the Fourth if you’re either writing for a U.S. audience or making some reference to the U.S. holiday. We would capitalize in this case wherever we were because it’s significant that the attackers chose Independence Day to target government websites. If we were writing for, say, a British audience about some unrelated event that just happened to take place on the fourth of July, we would not capitalize “fourth.”

Here’s a little joke I stole from BigMitch:

Q: Do they have the Fourth of July in England?

A: No, they just go straight from the third to the fifth.

End of joke, as my mom would say: Laugh here.

Admittedly, Big Mitch’s blog isn’t really about writing. If you’re looking for more grammar, here are some additional capitalization rules.

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