In the mid-twentieth century, the presence of Chinese and Japanese populations in North America and of South Asian populations in the Caribbean and South Africa is best explained

Some connecting rods have to lubricate the cylinder wall or piston pin. the answer is letter d. graphite coating can be a major  additive to many  coating  systems and things such as connecting rods.  it functions as a refractory, lubricant, thermal conductor, and electrical conductor for a machine or thing to enhance its work.

Cars should be kept indoors their entire life as to not get kidnapped, get diseases, run away from owner, or get eaten by a predator