Four Patterns Can Be Noted for Certain Organic Reactions: Pattern

Four patterns can be noted for certain organic reactions: Pattern 1: Add a proton.
Pattern 2: Take a proton away.
Pattern 3: Reaction between an electrophile and nucleophile to form a new covalent bond.
Pattern 4: Reaction of a proton donor with a carbon-carbon double bond to form a new covalent bond.
To which pattern does the following reaction belong?

A) Pattern 1
B) Pattern 2
C) Pattern 3
D) Pattern 4