Both drugs and dietary supplements can cause serious medical problems if used incorrectly.

Both drugs and dietary supplements causing serious medical problems if

used incorrectly is True.

This is because certain drugs aren't to be used together as the effect may be

very fatal. This is the reason why drugs have contra-indications in its leaflet

which explains how the drug should be used and which compounds must be

avoided during its use.

It is possible for a dietary supplement to contains compounds which could

trigger an adverse reaction when the drug are used. This explains why there

could be serious problems if both are used incorrectly.

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i think the answer would be b.