question: @ Override public Enumeration < Option > listOptions ( ) { Vector < Option > newVector = new Vector < Option > ( 5 ) ; newVector . addElement ( new Option ( "\tChoose attribute to be used for selection." , "C" , 1 , "-C <num>" ) ) ; newVector . addElement ( new Option ( "\tNumber of values to retain for the sepcified attribute, \n" + "\ti.e. the ones with the most instances (default 2)." , "N" , 1 , "-N <num>" ) ) ; newVector . addElement ( new Option ( "\tInstead of values with the most instances the ones with the \n" + "\tleast are retained.\n" , "L" , 0 , "-L" ) ) ; newVector . addElement ( new Option ( "\tWhen selecting on nominal attributes, removes header\n" + "\treferences to excluded values." , "H" , 0 , "-H" ) ) ; newVector . addElement ( new Option ( "\tInvert matching sense." , "V" , 0 , "-V" ) ) ; return newVector . elements ( ) ; }
target:  Returns an enumeration describing the available options.