I’m not sure if you meant “convince” and I don’t know the options giving but you can use words like persuade or prove or etc.
Answer:
The pressure of rising population and more workers on the supply of land
Explanation:
If the government introduces plan to improve technology and extend physical capital, this will result in the development of a country. If a country is facing a problem of high population growth rate then these developments will be off set. The excess of land will be used by increased population and enhancement in physical capital will be temporary as it will be offset by rising population pressure.
It's A. subordinate because it begins with a subordinate conjunction "because" and its adverbial clause since it asks the question "why?"
