Which of these is a hard soap?

Hard soap or curd soap is a kind of soap; examples are Aleppo soap, Castile soap, and Marseille soap or savon de Marseille. During the preparation of the soap, common salt (sodium chloride) is added to the liquid soap mass. This leads to the soap mass separating from glycerin, resulting in a harder soap. It can be made using sodium hydroxide.

Marseille soap or Savon de Marseille is a traditional hard soap made from vegetable oils that has been produced around Marseille, France, for about 600 years. The first documented soapmaker was recorded there in about 1370. By 1688, Louis XIV introduced regulations in the Edict of Colbert limiting the use of the name savon de Marseille to olive oil based soaps. The law has since been amended to allow other vegetable oils to be used.

By 1913 production had reached 180,000 tons, and in 1924 there were 132 soapmaking companies in the Marseille and Salon-de-Provence areas combined, but by 2000 only five remained.