What is the meaning of "shell resources" of listed companies?

For example, Company A wants to go public to raise funds, but according to the regulations of the CSRC, it cannot meet the conditions for listing (for example, it requires assets to reach a certain amount and make profits for three consecutive years).

So A obtains the controlling stake of listed company B through acquisition and asset replacement, so that company A can issue shares to raise funds through B (because B has this qualification). In other words, Company B is the "shell" of Company A's financing in the stock market.

A company like B is called Shell Resources.