Directions (26-30): In each question, four words are highlighted. One out of four words may or may not be misspelled. Choose the misspelled word, if any, as your answer.

Unlawful incursion has been thretening the safety of computer network system.

The correct answer is thretening.

Step-by-step Explanation:

Let's analyze the highlighted words in the sentence: "Unlawful incursion has been thretening the safety of computer network system."

1. Incursion: Correctly spelled. It means an invasion or inroad, especially an incursion into someone else's territory.

2. thretening: Incorrectly spelled. The correct spelling is threatening (with an 'a' in "threat"). It means stating an intention to inflict pain, injury, damage, or other hostile action.

3. safety: Correctly spelled. It refers to the condition of being protected from or unlikely to cause danger, risk, or injury.

4. network: Correctly spelled. It refers to a group or system of interconnected people or things.

Therefore, the misspelled word is thretening.