Question

why are the means of transport and communication called the lifelines of a country

Answer 1

because they help us to move from one place to another place ... and they are also used for emergency situations too...

preconditions for progress and development

A country 's economy depends not only on the production and sale of goods and services, but on their transport as well.

may be for that

Answer 2

without transport communication and transportation will not be held... without travelling from one place to another and without speaking to somebody ,there has been a trouble survival in every citizen of a country.