Sentence:  In late 1957 the M.P. ( Mouvement Populaire ) appeared and in the spring of 1958 the internal strains of the Istiqlal was revealed when the third Council of Government under Balafrej was formed without support from progressive <WSD>elements</WSD> in the party . 
Meaning of the word marked with <WSD> tags:  the most favorable environment for a plant or animal