which of the following is the longest

motive
cadence
climax
phrase

The longest of the following options is the "phrase."

what is the focal point in a melody

The focal point in a melody is typically referred to as the "climax." It is the highest or most intense point in the melody where the tension and emotional intensity reach their peak before resolving.

what's a phrase

In music, a phrase refers to a short musical idea or grouping of notes that forms a complete musical thought. It is like a musical sentence or a small section within a larger musical composition. Phrases often have a beginning, middle, and end, and they play an essential role in creating musical structure and conveying musical ideas.

a cadence marks?

A cadence marks the end of a musical phrase or section. It is a harmonic progression or sequence of chords that brings a sense of resolution or closure to the music. Cadences are like punctuation marks in music, indicating the end of a musical idea or providing a temporary pause before moving on to the next section. There are various types of cadences, such as the authentic cadence, plagal cadence, half cadence, and deceptive cadence, each with its own distinctive sound and effect.