The correct answer is indeed option 1, that the cells in a meristem of a plant have a dense cytoplasm, thin cell wall, large nuclei and the absence of vacuoles. Here`s the breakdown of each option:

Option 1: This is the correct answer because meristem cells are cells that have the ability to divide and differentiate into various types of plant cells. They contain a dense cytoplasm, large nuclei, and thin cell walls to allow for rapid cell divisions and growth. Also, the absence of vacuoles allows for more space for these activities.

Option 2: Although this option has the correct cytoplasm, cell wall, and nuclei characteristics, the large vacuoles are not consistent with meristem cells, which typically lack vacuoles as they still have to differentiate.

Option 3: This option incorrectly suggests that meristem cells have small nuclei. Meristem cells have large nuclei due to their high metabolic activity and their role in cell division.

Option 4: Similar to option 3, this option incorrectly suggests meristem cells have small nuclei. It also incorrectly states that meristem cells have thick cell walls. Having a thick cell wall would make it challenging for the cells to undergo rapid division.