has risen vs. has been rising

They are both correct, but "has risen sharply" would be closer to meaning a one-time price increase. Like "The price of gasoline has risen sharply since yesterday."
"has been rising" would mean a series of price increases.

1) The oil price has risen sharply in the last few weeks.
Simple past tense.

2) The oil price has been rising sharply in the last few weeks.
Implies a continuing action.

1) The oil price has risen sharply in the last few weeks.
Simple past tense.

2) The oil price has been rising sharply in the last few weeks.
Implies a continuing action.

Both are ok but carrying different meaning.