For the purposes of medical treatment only, the categories of drugs that can be legally prescribed listed from most to least restrictive ) otc, rx, v, iv, iii, ii, ib) otc, v, iv, iii, ii, i, rxc) i, ii, iii iv, v, rx, otcd) ii, iii, iv, v, rx, otc

d) II, III, IV, V, Rx, OTC

Explanation:

Based on its potential lethality, harm, addiction potential etc. drugs can be divided into five groups (drug schedule). Schedule I drugs are most restrictive and are not used in treatment and have extremely high addiction potential (heroin, for example). They are illegal substances and are not used in medical treatment. Going down to schedule V drugs are becoming less and less harmful and restricted with less potential for abuse.

Rx drugs are the ones that require a prescription in order to be purchased in the pharmacy.

OTC drugs are, so-called "over the counter" drugs, which can be purchased without prescription, making them the least restrictive.

So, the correct streak, from most to least restrictive drug, is:

II -> III -> IV -> V -> Rx -> OTC