I want to know the best route for road trip from Philadelphia to La Verne.
Meng, to answer your question, there are three major routes between Philadelphia and La Verne, California. For all three routes, you'll start off taking Interstate 70/76 (the Pennsylvania Turnpike) along southern Pennsylvania. In far western Pennsylvania, you'll have the option of taking I-76 when it splits off and goes north, and then picking up I-80 just west of Youngstown, Ohio.
Or, if you stay on I-70, you'll follow it at least until St. Louis. From there, you can take I-70 until you hit I-15 in Utah, or take I-40 through a more southern route.
On any of these routes, you're going to get parts of Pennsylvania, Ohio, Indiana, and Illinois. The question, then, becomes, which of the following choices would you prefer:
A) Iowa, Nebraska, Colorado, Utah, Arizona, Nevada, California
B) Missouri, Kansas, Colorado, Utah, Arizona, Nevada, California
C) Missouri, Oklahoma, Texas, New Mexico, Arizona, California
I should add that routes A and B are identical from the point where I-70 and I-80 meet in Colorado. But I'd probably take C, because it contains part of the old Route 66! Happy travels.