I want to open a business please suggest me which business is more profitable? -

1) import air conditioning do installation, servicing and repairation2) import tyres and sell in my country3) open a spare parts

There is insufficient information to conclude on which would be more profitable. It depends on what the level of competition is for each business, what the demand for each product is, what your pricing agreements are with your supplier, the margins for the various products.... etc. etc