The `Stand-Up India Scheme` correlates directly with option 3 - promoting entrepreneurship amongst women, SC (Scheduled Caste), and ST (Scheduled Tribe) communities. The purpose of the scheme is to encourage and support these underprivileged groups in starting their own businesses and enterprises, thereby fostering an entrepreneurial culture.

Here is a brief explanation of the other options:

Option 1 pertains to social security during old age. This option is incorrect because the Stand-Up India Scheme focuses on promoting entrepreneurship, not providing social security.

Option 2, providing technical knowhow to young, educated or skilled workers from rural areas, sounds similar to entrepreneurship but it`s not the same. It is more about skill development than entrepreneurship, hence it`s not the correct answer.

Option 4 talks about providing insurance cover to people aged between 18 and 50. This is unrelated to the Stand-Up India Scheme`s purpose of encouraging entrepreneurship.

Therefore, the only option that aligns with the aim of the Stand-Up India Scheme is option 3.