Choose the correct answer. They made ... mistakes in their test in French.

“Mistakes” is a countable plural noun, so it takes “many”, not “much”. To intensify “many” before a plural noun we use “so”: “so many mistakes”. “Such” is used with a noun phrase without “many” (“such a lot of mistakes”), so “such many” is wrong.

Manba: UZBMB namunaviy test topshiriqlari (2022, mutaxassislik)