In plants, water movement is

The correct option is: "down the potential gradient in both symplast and apoplast".

Water movement in plants is a passive process that is primarily driven by differences in water potential. Water potential (denoted by the Greek letter Psi, $\Psi$) is a measure of the free energy of water per unit volume. Water always moves spontaneously from an area of higher water potential (less negative/closer to zero) to an area of lower water potential (more negative). This is described as moving down the water potential gradient.

In plants, water travels from the roots to the leaves through two main pathways:
1. The Apoplast pathway: Water moves through the non-living parts of the plant, such as the cell walls and intercellular spaces, without crossing any cell membranes.
2. The Symplast pathway: Water moves through the living parts of the plant, crossing cell membranes and traveling from cell to cell via cytoplasmic connections called plasmodesmata.

Regardless of whether water is moving through the apoplast (external to the protoplasts) or the symplast (internal to the protoplasts), the fundamental physical force driving this movement remains the same. In both pathways, water moves passively down a potential gradient, flowing from regions of higher water potential to regions of lower water potential.