Spot the one that does not fit

Exercise and reference answers

Questions

1. Items

   1. Iron
   2. Nitrogen
   3. Potassium
   4. Calcium

   Odd item

   Iron

2. Items

   1. Sodium
   2. Silicon
   3. Zinc
   4. Cobalt

   Odd item

   Zinc

3. Items

   1. Chlorosis
   2. Necrosis
   3. Stunted growth
   4. Hydroponics

   Odd item

   Hydroponics

4. Items

   1. Rhizobium
   2. Frankia
   3. Anabaena
   4. Alnus

   Odd item

   Alnus

Instructions

Tap the item that does not belong with the rest.

Explanation