Question

insert one comma to separate the coordinate adjectives. as we strolled along the aged cobblestone walkway that meandered through the rose garden, we gazed at the array of fragrant colorful blossoms.

Explanation:

Coordinate adjectives are adjectives that modify a noun equally and can be joined by 'and'. 'Fragrant' and 'colorful' are coordinate adjectives modifying 'blossoms', so a comma should be inserted between them.

Answer:

As we strolled along the aged cobblestone walkway that meandered through the rose garden, we gazed at the array of fragrant, colorful blossoms.