What are the effects of excessive consumption of caffeine?

Identify the correct statements from the following:
$(i)$ With repeated use of drugs,the tolerance level of the receptors present in the body increases.
$(ii)$ Youngsters often use drugs repeatedly due to financial gains.
$(iii)$ Lack of proper guidance or counseling leads individuals to become addicts.
$(iv)$ Repeated use of alcohol leads to 'withdrawal syndrome'.

Cocaine or coke interferes with the transport of which neurotransmitter?

Unpleasant withdrawal syndrome occurs due to:

Which drug is obtained from opium?

Caffeine,cocaine and amphetamine are