Table:
0
A
B
C
D
1
product category code
product category description
unit of measure
reference product categories
2
Herbs
Herbs
Handful             
3
Seeds
Seeds
Weight - pound,kilo.
4
Spices
Spices
Weight - pound,kilo.

Questions and formulas:
Question: the herbs' measure unit
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:D1,A1="herbs"),3))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:D4,A2:A4="herbs"),3))
Level: medium
Question: spice descriptions
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:D1,A1="spices"),2))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:D4,A2:A4="spices"),2))
Level: medium
Question: Spices products
Formula: FILTER(A1:D1, A1="spices")
Formula2: FILTER(A2:D4, A2:A4="spices")
Level: easy
Question: The product description and unit of measure of herbs category code.
Formula: LET(query1,FILTER(A1:D1,A1="herbs"),UNIQUE(CHOOSECOLS(query1,2,3)))
Formula2: LET(query1,FILTER(A2:D4,A2:A4="herbs"),UNIQUE(CHOOSECOLS(query1,2,3)))
Level: hard
Question: the description of spices
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:D1,A1="spices"),2))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:D4,A2:A4="spices"),2))
Level: medium
Question: The spices product.
Formula: FILTER(A1:D1, A1="spices")
Formula2: FILTER(A2:D4, A2:A4="spices")
Level: easy