Measure first 4 ingredients into large bowl. Stir. Make a well in centre.
Combine next 3 ingredients in small bowl. Add apple. Stir. Add to well. Stir until just moistened. Fill 12 greased muffin cups 3/4 full.
Topping: Combine first 3 ingredients in small bowl. Cut in margarine until mixture resembles coarse crumbs. Sprinkle on batter. Bake in 400ºF oven for 15 to 20 minutes until wooden pick inserted in centre of muffin comes out clean. Let stand in pan for 5 minutes. Remove muffins from pan and place on wire rack to cool.