a) KaTeX parse error: KaTeX doesn't work in quirks mode.

b) KaTeX parse error: KaTeX doesn't work in quirks mode.

c) KaTeX parse error: KaTeX doesn't work in quirks mode.

d) KaTeX parse error: KaTeX doesn't work in quirks mode.

correct answer is: d) KaTeX parse error: KaTeX doesn't work in quirks mode.
Formula use: KaTeX parse error: KaTeX doesn't work in quirks mode.

Explanation

Here, given expression is KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
Now, put the value of KaTeX parse error: KaTeX doesn't work in quirks mode. and KaTeX parse error: KaTeX doesn't work in quirks mode. we get KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
Ans: KaTeX parse error: KaTeX doesn't work in quirks mode.