When buying short-term options and selling long-term options:

Position characteristics:

• Negative theta: Buying options (especially short-term) results in negative time decay
• Negative vega: Selling long-term options (which have higher vega) dominates the vega exposure
• Positive gamma: Buying options (especially short-term) gives positive gamma

Analysis of other options:

• (A) Sell short-term + sell long-term: Positive theta, negative vega, negative gamma
• (B) Sell short-term + buy long-term: Positive theta, positive vega, negative gamma
• (D) Buy short-term + buy long-term: Negative theta, positive vega, positive gamma

This strategy is typically used when expecting large price movements in the near term but stable volatility in the longer term.