Explanation:

Casting is a manufacturing process in which a molten material is poured into a mould to create a specific shape. The success of the casting process depends on various factors, including the properties of the moulding sand used. The following properties of moulding sand are essential for a successful casting process:

1. Permeability:
Permeability is the ability of moulding sand to allow gases and steam to escape during the casting process. If the moulding sand is not permeable enough, it can trap gases and cause defects in the final product. Therefore, permeability is an essential property of the moulding sand for a successful casting process.

2. Strength:
Strength is the ability of the moulding sand to resist deformation and breakage during the casting process. If the moulding sand is not strong enough, it can break and cause defects in the final product. Therefore, strength is another essential property of the moulding sand for a successful casting process.

3. Deformation:
Deformation is the ability of the moulding sand to resist compression and maintain its shape during the casting process. If the moulding sand deforms too much, it can cause defects in the final product. Therefore, deformation is another property that is essential for the moulding sand.

4. Flowability:
Flowability is the ability of the moulding sand to flow and fill the mould cavity during the casting process. If the moulding sand is not flowable enough, it can cause incomplete filling of the mould cavity and result in defects in the final product. Therefore, flowability is another important property of the moulding sand.

5. Refractoriness:
Refractoriness is the ability of the moulding sand to withstand high temperatures without melting or deforming. If the moulding sand is not refractory enough, it can melt or deform during the casting process and cause defects in the final product. Therefore, refractoriness is also an important property of the moulding sand.

Considering all the above properties, option B is the correct answer, which includes all the properties mentioned above (1, 2, 3, 4, and 5). Therefore, all these properties are essential for the moulding sand to ensure a successful casting process.