在JavaScript中，页面中显示当天日期“今天是2013年9月1日”，下列选项正确的是( )
A.var today;today=new Date( );
document.write("今天是"+today.getYear( )+"年"
+(today.getMonth( )+1)+"月"+today.getDay( )+"日");
B.var today; today=new Date( );
document.write("今天是"+today.getFullYear( )+"年"
+(today.getMonth( )+1)+"月"+today.getDay( )+"日");
C.var today;
Today=new Day( );
document.write("今天是"+today.getFullYear( )+"年"
+(today.getMonth( )+1)+"月"+today.getDate( )+"日");
D.var today;
today=new Date( );
document.write("今天是"+today.getFullYear( )+"年"
+(today.getMonth( )+1)+"月"+today.getDate( )+"日");
正确答案D 