Avolatile
Bfriend
Cextends
Dthis
Correct Option: 3
Explanation:
extends is not a valid keyword in C++, all the rest are valid keywords of C++.
List of C++ Keywords
alignas alignof and and_eq asm atomic_cancel atomic_commit atomic_noexcept auto bitand bitor bool break case catch char char16_t char32_t class compl concept const constexpr const_cast continue co_await co_return co_yield decltype default delete do double dynamic_cast else enum explicit export extern false float for friend goto if import inline int long module mutable namespace new noexcept not not_eq nullptr operator or or_eq private protected public register reinterpret_cast requires return short signed sizeof static static_assert static_cast struct switch synchronized template this thread_local throw true try typedef typeid typename union unsigned using virtual void volatile wchar_t while xor xor_eq
