Option 1: Safe -> Free from danger or risk; the direct opposite of perilous.
Option 2: Hazardous -> Dangerous or risky; this is actually a synonym of perilous, not an antonym.
Option 3: Deep -> Refers to distance or profundity; unrelated to the concept of danger.
Option 4: Intense -> Means extreme or strong; not opposite in meaning to perilous.
Hence, Option 1: Safe -> "Perilous" means dangerous or full of risk, so its opposite would be "safe," which means free from danger or harm -> correct